CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Wenxiu Jiao,Jiaxing Zhang,Zhiyong Zhang,Aimin Sha,Meng Jia
Adding phase change materials (PCMs) to asphalt pavements can effectively reduce temperature sensitivity and delay snow and ice accumulation. This study aims to develop solid-solid phase change materials (SSPCMs) for asphalt pavements, with a focus on winter road de-icing. First, the suitability of polyethylene glycol (PEG) and polytetramethylene ether glycol (PTMEG) with varying molecular weights as soft segments was systematically evaluated based on phase change performance, thermal stability, phase change cycling stability, and specific heat capacity. SSPCMs were synthesized using a two-step solution polymerization method, with successful synthesis confirmed by FTIR analysis. The influence of different soft-to-hard segment ratios on phase change performance was also examined. PTMEG2000 exhibited excellent performance, with an exothermic phase change temperature range from 8.5°C to -1.2°C and an enthalpy of 94.3 J/g. Its thermal decomposition onset temperature was 266.05°C, and its performance remained stable after 20 thermal cycles. The incorporation of hard segments led to a reduction in both phase change enthalpy and the initial phase change temperature. At a molar ratio of 4,4′-diphenylmethane diisocyanate (MDI) to PTMEG2000 of 2.4:1, the phase change temperature range was 4.1°C to -5.1°C, with an enthalpy of 37.1 J/g, demonstrating great potential as a de-icing material for roads in cold climates.
研究领域:
材料科学
·
土木工程
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Xiao Yang,Jinxiang Hong,Zijia Xiong,Wei Liu,Minghui Gong,Jinliang Cheng,Zhenghong Xu,Chuanqing Fu
Polyurethane (PU) is recognized as a promising material for asphalt modification due to its tunable physicochemical properties. To reduce reliance on petroleum-based polyols, this study employed bio-derived castor oil (CO) combined with polytetrahydrofuran (PTMEG), diphenylmethane diisocyanate (MDI), and 1,4-butanediol (BDO) as raw materials. Polyether-type PU (PTMEG-MDI) and polyether/castor oil composite PU (PTMEG/CO-MDI) were successfully synthesized through controlled hard segment content ( C h ) and isocyanate index ( r ), followed by application in asphalt modification. The structure-property relationships were investigated using FTIR, TGA, DSC, and mechanical testing systems. The results demonstrated that the incorporation of CO significantly enhanced the comprehensive performance of PU composites. Compared to the single polyether-type PU, the PTMEG/CO composite PU exhibited better thermal stability, mechanical strength, and elongation at break. Increasing C h continuously improved the Shore hardness and tensile strength of PU, while reducing its thermal stability and elongation at break. When r reached 1.2, the PU molecular chains attained an optimal stability equilibrium state. FTIR analysis confirmed chemical reactions between the -NCO groups in PU and active components of asphalt, forming characteristic urethane absorption peaks, thereby achieving chemical bonding modification. In terms of asphalt modification performance, the PTMEG/CO-MDI system notably enhanced high-temperature stability while maintaining favorable low-temperature performance. This research establishes fundamental correlations between PU molecular design parameters ( C h and r ) and asphalt modification performance, providing theoretical guidance for developing eco-friendly high-performance asphalt modifiers.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2022
·Vol. 308
·期 4
·2200547
·
IF 4.402
Peng Fu,Jiahui Zhang,Yuancheng Zhang,Wei Zhao,Xiaomeng Zhang,Ge Shi,Yanjie He,Zhe Cui,Xinchang Pang,Minying Liu
Shape memory polyamide elastomers have attracted large attention owing to a variety of favorable properties (e.g., designable chemical structure, good thermal stability, flexibility, and elasticity, et al). However, the polyamide elastomer reported recently still lack good mechanical property. In the present work, a new type of shape memory thermoplastic polyamide elastomer (TPAE), composed of long carbon chain PA1212 and polytetramethylene ether glycol (PTMEG), is synthesized through two-step melt polycondensation, which is named as poly(ether- b -amide) (PEBA). The chemical structure of PEBA is confirmed by FTIR results and it also shows excellent mechanical properties. PEBA, possessing two melting temperatures, stay in microphase separation among PTMEG soft domains and PA1212 hard domains that are amorphous and α crystal, respectively. Furthermore, PEBA can fix a temporary shape after the heated strip is twisted and cooled down and then recover to the original shape after secondary heating, which is attributed to the fixing force provided by PTMEG domains and entropy elasticity of physically cross-linked PA1212 domains, respectively. Besides, PEBA elastomer can be reshaped between ≈190 and ≈380 °C and it also has shape memory behavior. This new kind of TPAE proposes a new smart material for sensors and soft robotics.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2021
·Vol. 32
·期 9
·3495-3504
·
IF 3.665
Kun Cong,Jiyu He,Rongjie Yang
TPU and flame-retardant TPU (FR-TPU) were prepared through a polyaddition reaction with polytetramethylene ether glycol (PTMEG) and 4,4′-methylene-bisphenyl-isocyanate (MDI) by reactive extruding. 1,4-Butanediol (BDO) and diethyl bis(2-hydroxyethyl) amino methyl phosphonate (DBAMP) were used as the chain extender in different ratios, respectively, to obtain TPU and flame-retardant TPU (FR-TPU)with adjusted molecular weight and mechanical properties. The resulting TPU and FR-TPU were characterized by FTIR, DSC, TGA, and NMR. A kinetic model based on the data from extrusion process was used to depict the polymerization of TPU. These reactions carried out without any solvent and the residual water showed that the polymerization with BDO could be achieved in 20 minutes, instead, that with DBAMP in 55 minutes while with a similar molecular weight. These results point out that Twin Screw Extrusion Reaction (TSER) is a suitable and convenient way to produce a variety of polymers.
研究领域:
材料科学
·
高分子化学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）